This is a retro recipe for a sponge cake with a caramelized coconut topping and is very tasty.  This version is adapted from Serious Eats.  It makes one 9 x 13 inch cake and takes about 90 minutes, mostly elapsed time.

For the cake

Non-stick cooking spray

4 Tbs. (half a stick) unsalted butter

¾ cup whole milk

4 large eggs

300 g. (1.5 cups) sugar

192 g. (1.5 cups) all-purpose flour

1.5 tsp. baking powder

1 tsp. Diamond Crystal kosher salt (or ½ tsp. ordinary salt)

For the topping

6 Tbs. unsalted butter

107 g. (1/2 cup) unsalted butter

¼ tsp. Diamond Crystal kosher salt (or ¼ tsp. ordinary salt)

¼ cup whole milk

198 g. sweetened coconut

Preheat the oven to 350 degrees.  Grease a 9 x 13 inch baking pan with cooking spray.

Combine the butter and milk for the cake in a small saucepan.  Bring to a gentle simmer and then allow to cool for about 5 minutes.

In the bowl of a stand mixer put the eggs and sugar.  With the whisk attachment, beat the eggs and sugar at medium-high speed until they have doubled in volume, about 7 minutes.

In a small bowl, mix together the flour, baking powder, and salt.

Reduce the mixer speed to low and slowly pour in the butter/milk mixture.  (No need to clean the pan since you will use it for the topping.)

Slowly add the dry mixture to the bowl of the stand mixer on low speed and mix until just combined, scraping the sides of the bowl to combine all the flour into the batter.

Pour the batter into the prepared pan and bake for 25 minutes until it is a light golden brown.

While the cake is baking, prepare the topping.  Start by melting the butter in the small saucepan over medium heat and cook it, whisking from time to time until the milk solids turn golden and the butter smalls nutty, about 4 minutes.  Reduce the heat to low and stir in the brown sugar and milk.  Bring to a simmer and stir until the sugar completely dissolves, about 2 minutes.  Remove from the heat and stir in the coconut.

After the cake has baked for 25 minutes, carefully remove it from the oven and spoon the topping over it.  With an offset spatula or the back of a spoon, spread the topping evenly over the cake.  Return the cake to the oven and bake another 20-25 minutes until the topping is nicely browned.